32bit vs 64bit guest VM and RAM usage

Posted by sims on Server Fault See other posts from Server Fault or by sims
Published on 2010-04-18T14:19:45Z Indexed on 2010/04/18 14:23 UTC
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Filed under:

architecture

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32bit-64bit

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memory-usage

Why does a 32bit domU (Xen guest VM) use less RAM than a 64bit?

Notes: The same software complied for a different arch(AMD64 vs. 686). Obviously this is Linux or BSD or something easily ported. Maybe this is also a good one for SO.

I've read this is so. I can guess why, but I'd like to hear everyone's comments.

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